Concept:Money has passed through different stages, including commodities, coins, and paper money.
Explanation:Coins were early metallic money used as a medium of exchange.
Inconvertible paper money is a type of currency not convertible into gold or silver.
Commodities such as cattle, salt, or cowries were used as money in early trade.
An abacus is a counting device used for arithmetic, not a form of money.
Therefore, it does not belong to the development of money.
Answer:D. Abacus